隧道(tunnel)
水平或接近水平的地下或水下通道。这种通道被用来采矿，尤其是作为火车或机动车的轨道来引导堤岸附近的江河、埋藏电站等机构的地下设施或引导水源等。古代人用隧道来进行灌溉或运送饮用水，在西元前22世纪，巴比伦人修建了隧道来实现幼发拉底河下的交通。罗马人修建了输水道隧道来用火迅速加热岩石或用水迅速冷却岩石，以使岩石裂开。17世纪开始使用火药爆破後，在岩石开采上有了质的进步。较软的岩石可以用开隧道的方法来实现，用转动的轮子来将物质开采出来并靠传送带运输出去。19和20世纪的铁路运输使隧道的数量和长度得到了很大提高。早期隧道主要用砖石来支撑，而现代隧道则以钢架为支撑，直到混凝土建筑的完成。一般的通道修筑方法包括在开采後立刻喷制混凝土来加固等。
English version：
tunnel
Horizontal or nearly horizontal underground or underwater passageway. Tunnels are used for mining, as passageways for trains and motor vehicles, for diverting rivers around damsites, for housing underground installations such as power plants, and for conducting water. Ancient civilizations used tunnels to carry water for irrigation and drinking, and in the 22nd century BC the Babylonians built a tunnel for pedestrian traffic under the Euphrates River. The Romans built aqueduct tunnels through mountains by heating the rock face with fire and rapidly cooling it with water, causing the rock to crack. The introduction of gunpowder blasting in the 17th century marked a great advance in solid-rock excavation. For softer soils, excavation is accomplished using devices such as the tunneling mole, with its rotating wheel that continuously excavates material and loads it onto a conveyor belt. Railroad transportation in the 19th-20th century led to a tremendous expansion in the number and length of tunnels. Brick and stone were used for support in early tunnels, but in modern tunneling steel is generally used until a concrete lining can be installed. A common method of lining involves spraying shotcrete onto the tunnel crown immediately after excavation.
